High-Entropy Melt of Lithium, Sodium, and Potassium Fluorides and Chlorides as a Possible Coolant for Molten-Salt Reactors

Suggestions are made for potentially promising coolants for molten salt reactors from a mixture of six lithium, sodium, and potassium fluoride and chloride salts having high entropy of mixing. These compositions, which contain less lithium salts, should have higher thermodynamic stability than FLiNaK or FLiBe because of their high entropy. The chemical formula of the maximum high-entropy solution, Li_1/6Na_1/6K_1/6F_1/4Cl_1/4, may result from mixing the variety of alkali halides like MX (M = Li, Na, K and X = F, Cl) taken in an equimolar ratio. Molecular dynamic estimations of the density, heat conductivity, and viscosity demonstrate reasonable values of these properties between those of the fluorides and chlorides.